In general, it has been known that a plastic lens for eyeglasses can be provided with antiglare and good visibility functions by mixing an organic coloring agent.
For example, spectacle lenses made of plastics which shield visible light rays with wavelength around 585 nm to lessen the unpleasantness and visual sense fatigue relevant to glare by selectively shielding the light rays in a wavelength band in which glare is felt.
Resins used for spectacle lenses include thermoplastic resins such as acrylic resins, polystyrene resins and polycarbonate resins, and also thermosetting resins such as allyl diglycol carbonate resins (also referred to as CR-39 resin or ADC resin), polyurethane resins, and polythiourethane resins, etc.
Such thermosetting resins are converted into lens materials by preparing raw material compositions by mixing raw material compositions with a catalyst, a curing agent, and if necessary a template agent, a resin reforming agent, an ultraviolet absorbing agent, an infrared ray absorbing agent, an antioxidant, etc.; degassing and mixing the mixtures; next, injecting the mixtures in molds of glass dies or metal dies; and thereafter polymerizing and curing the mixtures, and heat treatment is carried out for the polymerizing and curing.
As a catalyst usable for the polymerizing and curing, organic peroxides have been known and there are compounds broadly classified into diacyl peroxides, peroxydicarbonates, peroxyesters, peroxyketals, dialkyl peroxides, hydroperoxides, etc.
The CR-39 resin is obtained by curing a composition obtained by mixing diethylene glycol bisallyl carbonate, which is a monomer, with a peroxydicarbonate type peroxide (e.g. diisopropyl peroxydicarbonate) as a catalyst.
There is known a material provided with good balance between the antiglare property and visibility and thus having both functions of practical usability and color tone by adding an organic coloring agent such as an azaporphyrin compound to make a product lens have a main absorption peak in a range of 565 nm to 605 nm in a visible light-absorption spectroscopic spectrum (Patent Document 1).